I've watched all the NCIS episodes up until the most recent season. I realise there is more to them, just as there were to the Scoobies, but they do all still generally act rather buffoonish. Abby, for example, can be pretty annoying at times with her "Gibbs, Gibbs, Gibbs!" half informational, half digression, scatterbrained routine.

I'm happy for SHIELD to have the same light tone as something like Hawaii Five-0 or Castle, but not NCIS.

I wouldn't call them buffonish, Abby is quirky and wears her heart on her sleeve, but it's never implied that she is anything but whip smart at her job, same with Tony, his immaturity is like a shield. In the case of Hawaii Five-0 Steve and Danno have the same sorts of ticks, like the carguments gimmick where their rules vs blowing things up differences are a source of the bulk of the jokes. It's less so with Chin and Kono but that's because they aren't as developed at this point as the NCIS team.

__________________"Now this life is etched in black but I wont be looking back, the rain washed out the tracks, I'll never find again"